I have a client site where they are setting up dates in a calender table. Approx 90 URLs in the table which grab the time stamp, client ID & staffID and sent it to the database depending on which hour / minute you select.

The clientID and staffID at the moment are just taken straight from the DB. I need to encrypt change these so you cant just go in and change to a different client or staff. I wondered about using a timestamp when setting up the client ID and staff ID as two times are never going to be the same and it would be pretty difficult to guess a correct time stamp.